Kitchen Appliances · Buying Guide
Measuring Up for a Built-In Appliance: aperture, clearances and services
The most expensive mistake in a kitchen is buying a built-in appliance that does not fit. A built-in oven or hob has to drop neatly into an existing cabinet opening, sit with the right gaps around it, and reach the power or services behind it, and if any of those is wrong, the appliance goes back and the project stalls. A little careful measuring before you buy avoids all of it. This guide walks through exactly what to measure and why.
To measure for a built-in appliance, check three things. First, the aperture: the height, width and depth of the cabinet opening the appliance drops into, measured accurately, because built-in appliances are made to standard housing sizes and must match. Second, the clearances: the gaps and ventilation space the manufacturer requires around the appliance, plus room for the door to open and for the appliance to be slid in. Third, the services behind it: the electricity supply, and for some appliances water and waste, positioned so the appliance can reach them. Always check the specific model's installation dimensions, as these vary, before you buy.
We cover the three things that decide whether a built-in appliance fits and works: the aperture it drops into, the clearances it needs around it, and the services behind it. Get these right and installation is straightforward. Browse our cooking appliances and built-in ovens once you know your measurements.
Start with the aperture
A built-in appliance is designed to slot into a cabinet opening, so the first job is to measure that opening accurately in three dimensions: height, width and depth. Built-in ovens, hobs and similar appliances are made to standard housing sizes, so most kitchens are built around common openings, but you should never assume. Measure the actual opening in your kitchen, at more than one point, because cabinets are not always perfectly square, and note the smallest measurement in each direction. A few millimetres matter: an appliance that is fractionally too big will not go in, and one that is too small leaves ugly gaps.
For a hob, also measure the worktop cut-out, the hole in the worktop the hob sits into, separately from the cabinet below, as the cut-out size is what the hob is designed to drop into.
Allow the right clearances
Fitting is not just about the hole; it is about the space around the appliance. Manufacturers specify clearances for good reasons, and ignoring them causes overheating, doors that foul cabinets, and appliances that cannot be installed or serviced. Check for:
- Ventilation gaps: many appliances, especially ovens, need air space around or behind them to release heat, and the manufacturer states the minimum.
- Door and drawer swing: room for the oven door to open fully, or a dishwasher door to drop, without hitting an island or opposite units.
- Adjacent clearances: space beside the appliance so it is not jammed against a wall or another unit.
- Above a hob: the required distance between a hob and any extractor or unit above it, which is a safety clearance.
These clearances are in the installation instructions for the specific model, so they are worth checking before buying rather than discovering on fitting day.
Check the services behind the appliance
An appliance that fits the hole still has to connect to what it needs. Behind a built-in appliance there must be the right services, positioned so the appliance can reach them once it is pushed back into place:
- Electricity: a suitable power supply in the right position. Larger appliances such as many ovens and hobs need more than a standard socket and a dedicated circuit, which is covered in our guide to the electrical supply induction hobs need.
- Water and waste: for a built-in dishwasher, the water supply and drainage must be present and reachable.
- Space for connections: the services take up room behind the appliance, so allow for them within the depth so the appliance still sits flush.
Measuring the aperture
Measure height, width and depth at more than one point, and note the smallest figure in each direction. Built-in appliances are made to standard housing sizes, but a few millimetres out is enough to stop one going in cleanly.
Allowing the right clearances
Ventilation gaps, door swing, adjacent space and, above a hob, the distance to any extractor, all factor in. These figures live in the specific model's installation instructions, so check them before you buy.
Check the model, not just the category. Standard housing sizes are a good starting point, but installation dimensions and clearances vary from model to model. Before you buy, read the specific appliance's installation requirements and check them against your kitchen, rather than assuming any built-in oven or hob will fit any opening. Five minutes with the model's dimensions saves a return and a delay.
Buy the appliance that fits your kitchen
With the aperture, clearances and services measured and checked against the specific model, a built-in appliance goes in cleanly and works first time. If you are unsure what your opening will take, bring your measurements to us. Brennan's Electrical is an independent Irish appliance retailer with a physical store in Arklow, and our team can help you choose a built-in oven, hob or appliance that actually fits, from the brands we stock. Browse our cooking appliances and built-in ovens, and call the Arklow store on 0402 32870.
Frequently asked
How do I measure for a built-in oven or hob?
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Will any built-in oven fit my existing opening?
Not sure what will fit?
Bring your measurements to Brennan's Electrical in Arklow and we will help you choose a built-in appliance that fits first time. We stock built-in ovens and cooking appliances from the best brands in Ireland, with honest advice on what actually fits your kitchen. For general consumer advice on buying appliances, see the CCPC's guidance.